What happens when a heater motor resistor fails?
If the resistor shorts or fails, it may cause the blower motor to remain stuck on one fan speed. The heating and air conditioning systems may still function at one speed, however the resistor will have to be replaced in order for full functionality to be restored. 2. Blower motor does not work on certain settings
Why does heater blower motor increase in resistance?
As part of our comfort and luxury, the blower speed is one of the most adjusted settings in a car, and so the resistance of the blower motor is constantly being put under stress, which can eventually lead to motor failure; too much humidity in the atmosphere can lead to an increase in resistance.
What are the symptoms of a failed blower motor resistor?
Blower motor resistor problems. Problems with a blower motor resistor are common in many cars. The most common symptom of a failed blower motor resistor is when the heater fan only runs at high speed and doesn’t work at low speeds.
Is the speed of the blower controlled by the resistor?
The blower speed can be adjusted in almost every modern car. Some cars have blowers that have 4 to 5 fixed speed settings that can be selected, but in this case, the speed of the blower motor is controlled by a blower motor resistor. 1. No air blowing through vehicle’s vents
If the resistor shorts or fails, it may cause the blower motor to remain stuck on one fan speed. The heating and air conditioning systems may still function at one speed, however the resistor will have to be replaced in order for full functionality to be restored. 2. Blower motor does not work on certain settings
The blower speed can be adjusted in almost every modern car. Some cars have blowers that have 4 to 5 fixed speed settings that can be selected, but in this case, the speed of the blower motor is controlled by a blower motor resistor. 1. No air blowing through vehicle’s vents
As part of our comfort and luxury, the blower speed is one of the most adjusted settings in a car, and so the resistance of the blower motor is constantly being put under stress, which can eventually lead to motor failure; too much humidity in the atmosphere can lead to an increase in resistance.
Blower motor resistor problems. Problems with a blower motor resistor are common in many cars. The most common symptom of a failed blower motor resistor is when the heater fan only runs at high speed and doesn’t work at low speeds.
What to do if your AC heater fan is not working?
AC/Heater Blower Fan not Working – Motor or Resistor? Quick Fix If playback doesn’t begin shortly, try restarting your device. Videos you watch may be added to the TV’s watch history and influence TV recommendations. To avoid this, cancel and sign in to YouTube on your computer.
Why is the resistor not working on my blower?
Hi There, The resistor is what controls the speed of the blower motor, not the relay. The blower motor relay supplies power to this motor when you turn the switch to “on” that can sometimes fail. When this happens, you may notice that you will not feel anything blowing out of the vents at all.
What causes a blower fan to not work?
When this happens, you may notice that you will not feel anything blowing out of the vents at all. This may also cause the blower motor to work intermittently. A blower fan is connected to the negative battery terminal (also called ground) on one end and to the positive battery terminal through a blower motor resistor on the other end.
Why is my heater blower motor resistor not working?
This occurs due to the failed blower motor resistor not being able to control the flow of electric current, it could be that the resistor is somehow bypassed and the power is directly being fed from the switch. Excessive current can overheat and permanently damage the blower motor resistor
AC/Heater Blower Fan not Working – Motor or Resistor? Quick Fix If playback doesn’t begin shortly, try restarting your device. Videos you watch may be added to the TV’s watch history and influence TV recommendations. To avoid this, cancel and sign in to YouTube on your computer.
What does the resistor on a heater do?
It is responsible for controlling the blower motor’s fan speed. When fan speed is changed via the knob on the instrument cluster, the blower motor resistor changes setting, which changes the speed of the blower motor.
Where can I get a new blower motor resistor?
I replaced the blower motor resistor and the control unit with new parts from rockauto (ACDelco). I’ve checked the fuse in the dash fuse panel and it is good.
When does a blower motor resistor need to be replaced?
If the resistance is out of specs, the resistor must be replaced. For example, in this photo we measured the resistance of this blower motor resistor. According to the service manual, it must be around 4-5 ohms. In our case the ohmmeter shows open circuit, which means the resistor has failed.
What are the different types of resistors available?
Resistors are available in different shapes and sizes. Common types that are available are through-hole and surface mount. A resistor might be static, standard resistor, special, or a pack of variable resistor. There are two basic types of resistors as follows: Linear resistor.
Can a designer use more than one sense resistor?
Designers are sometimes forced to use more than one current sense resistor connected in parallel, either to meet a high power or surge rating, or to achieve an ohmic value lower than the minimum available. This is problematic but possible.
What happens when a blower motor resistor fails?
The blower motor resistor is the component directly responsible for controlling the blower motor fan speed. If the resistor shorts or fails, it may cause the blower motor to remain stuck on one fan speed.
What should I consider when buying a resistor?
Cost: Cost is a major consideration when buying resistors. Particularly for private individuals this may be one of the most important considerations. Normally quality is good, but this needs to be taken into account especially when prices are low. Normally though quality is very good.
What are the symptoms of a bad heater motor resistor?
Symptoms of a Bad or Failing Heater Blower Motor Resistor. 1 1. Blower motor stuck on one speed. A common symptom of a faulty blower motor resistor is a blower motor that is stuck on one setting. The blower 2 2. Blower motor does not work on certain settings. 3 3. No air from the vehicle’s vents.
What are the symptoms of a bad cooling fan resistor?
Another symptom of a potential problem with the cooling fan resistor is cooling fans that stay on at all times. If the resistor shorts or fails, it can cause the cooling fans to stay on even when they are not supposed to.
Why is my blower motor resistor not working?
If there is power indicated on high blower speed, but not low or mid range, the problem is the blower resistor. Test for ground at the blower motor if there is power indicated at all ranges, but the motor does not function.
Why does my blower fan only work on one speed?
by Lee Sallings. The most common symptom of a faulty blower motor resistor is a blower fan that only works on one speed, usually high. This can be annoying, but troubleshooting is easy. If you start at the blower motor, and check resistance in the circuit, you will find the problem in no time.
Where is the resistor on an air conditioner fan?
The air conditioning and heating controls allow you to switch fan speeds — and the blower motor resistor controls that speed once you select it. The resistor is between the power source and the fan, and allows only the desired amount of power to go to the fan.
What do you call the fan that spins the heater?
When the heater or air conditioner in your car is turned on, the fan turns on pushing the air from the car vents. The motor that spins that fan is called a blower motor.
When this happens, you may notice that you will not feel anything blowing out of the vents at all. This may also cause the blower motor to work intermittently. A blower fan is connected to the negative battery terminal (also called ground) on one end and to the positive battery terminal through a blower motor resistor on the other end.
How does a high speed blower motor work?
In the highest fan speed state, the blower resistor is bypassed completely and the fan is effectively connected directly to the car’s battery, allowing maximum current to be supplied to the blower motor.
Why is my blower motor stuck on one speed?
Blower motor stuck on one speed A common symptom of a faulty blower motor resistor is a blower motor that is stuck on one setting. The blower motor resistor is the component directly responsible for controlling the blower motor fan speed. If the resistor shorts or fails, it may cause the blower motor to remain stuck on one fan speed.
How is a step resistor used in a fan?
A voltmeter connected to both ends of a resistor while current is passing through it to a load will measure the amount of voltage being “dropped” by the resistor. Because lower voltage means lower current delivered to the fan, the stepped resistor circuit can be used to control fan speed.
Why are there so many resistors on a blower switch?
The blower switch and its gang of resistors are wired so that when the blower switch is set at the lowest speed, the maximum amount of voltage is dropped and the least amount of current is fed to the motor because it is passing through an entire series of resistors – for our purposes we’ll say there are three resistors.